Formatted numeric output: Difference between revisions

Behaviour of <code>format ( $ a b --> $ )</code>

Accepts a well formatted numerical string <code>$</code>, optionally with a decimal point, without validation.

<code>a</code> is the number of digits before the decimal point. <code>b</code> is the number of digits after the decimal point.

Returns a string <code>$</code> with either a leading zero or a leading space, then ''at least'' <code>a</code> digits, then a decimal point, then ''at least'' <code>b</code> digits. The digits are padded with zeroes fore and aft if required.

"''at least''" – if there are already more digits before the point than <code>a</code>, and/or more digits after the point than <code>b</code>, it will ''not'' crop the number. IMO, it is better to mess up the formatting than to display an incorrect number. Check the $ is not too long fore or aft before passing to <code>format</code> if the string may be truncated.

<syntaxhighlight lang="Quackery"> [ over find swap found ] is has ( $ c --> b )

[ dip [ behead drop ]

swap iff char -

else space

swap join ] is left-pad ( $ n --> $ )

<pre> 00007.125

-00007.125

00000.125

-00000.120

00007.120

-00007.120

00000.120

-00000.120

00007.000

-00007.000

00000.000</pre>